Rotary compressor



May 3, 1927. 1,626,768

C. W. VOLLMANN ROTARY COMPRESSOR- Filed March 8. 1926V 2 Sheets-Sheet-'1l IDI WJ 1K 2 Sheets-Sheet 2 c. w. VOLLMANN ROTARY COMPRESSDR Filed Marh8, 1926 Patented May 3, 1927. l

UNITED STATES Aram" oFFc-E.

CARL VOLLMANN,0-F MONTREALQUEBEC, CANADA.

ROTARY COMPRESSOR.

Application led'uMarch 8, 1926. Serial No. 93,184.

My invention relates particularly to rotary gas'compressors of the typein which a lubricating circuit is included and has for Its object toprovide a self-contained compact machine which will embody the gascompressor members and the 'lubricating circuit within a singlecylinder, and provide greater security for the' How of the oil.

To 'this end the invention broadly stated consists of a cylindrical oilchamber contained within the cylinder and containing rotary gascompressing members, the cylinder being so constructed as to present arelatively shallow oil chamber within the cylinf der beneath thecylindrical oil chamber, and

having' in connection therewith a vertical v oil and gas passage betweenthe inner end Figure 2 is an axial vertical sectional viewtaken online-2 2 Figure 1;

Figure 3 is a vertical sectional View taken on line 3-3 Figure 1;

Figure .L1 is a transverse vertical sectional view taken on line 4-f4Figure '2;

Figure 5 is a top or plan view of my improved rotary compressor;

Figure taken on line 6-6 Figure 1; t

Figures 7, 8, and 9 'are details of the surrounding andintercommunicating oil channels;

Figures 1() and 11 illustrate lin longitudinal and transverse sectional4'views respec-l tively, the encircling oil chambers 'for spreading theoil between the' adjacent fric-v tion surfaces;

Figure 12 being a perspective view of the end of one of the shafts to-indicate the transverse groove forintercommunication with/ theencircling chambers; and

Figure 13 is a ,diagrammatic view of a 6 isa horizontal' sectional view`refrigerating system with my invention applied thereto.

Rotary compressors as heretofore constructed have employed an externalsystem of lubrication and separation of the oil from the gas.- That isto say the body of the lubricant is-carried outside and independently ofthe compressor and connected to the latter bya system of .externalpiping in connection with ducts| leading through the frame of themachine to the'points where lubrication is required.-

. According to my present invention the rotary compressor is equippedwith intermeshing spiral gears of cylindrical forni mounted inintel-meshing relation on a pair of shafts b and o journalled at one endin .the cylinder head d and the opposite end inv the head e of the gearcase f carried by the cylinder head d. This gear case is enclosed by aninternal oil chamber g forming an integral part of the cylinder h`uponwhich the cylinder head d is mounted. This cylinder has a base c'within.wl1ich a /main oil chamber j is formed and extends below andupwardly between the inner end of the internal oil chamber and the endwall k of the cylinder. The dividing wall g1 separating Athe internaloil chamber from the end of the cylinder has a gas port m near its upperend and an oil port n near its lower en d.

The gas port communicates with a gas and oil separator consisting of aseries of baer plates o, o1 and o2. 'Ihe first plate extends from a topplate o3 downward to a point below the port but above the oil level; thesecond plate extending from slightlyabove the level of the port 4to apoint below the level of the oil; the third plate extends, like thefirst plate, from the cover plate to a point below the port but abovethe oil level.

' The upper end of the chamber s between these walls carries a gasdischarge fitting t of the usual type'in compressors o f this class, thebottomof the outer oil'chamber is provided'at one cornerwith aY suctionport u protected'by a strainerl fv. The gas Icompressing spiral gears.and 'their operating.

mechanism contained within the gear'case are of usual vconstru'r-3tionand consist of the interemshng :cylindrical spiral gears 10, 12 andthe'intermeshing driving spiral gears 13 and 141 respectively,'separatedby a partition 16 having a port ,17 eifecting communication between thedischarge end o f the gears and 12 and the` suction end of the gears 13and 14. The respective pairs of gears communicate with suction chamber Vend' of the gear case.

' the gear 13 is free on its shaft.

and -discharge chamber 21 in` the cylinder head and a discharge port 22in the inner he gears 10, 12 and 14 are keyed to their respective shaftswhile The purpose of this arrangement is to ensure rotation of thecountershaft to augment the lubrication of the end of such countershaft.

The oil ducts are located one, 25, `in the end 26y of the cylinder andcommunicating at one end with the oil discharge port u and at itsopposite end through a port 27 with a port 28 leading obliguelv to theend of the bearing of the countershaft 29 carrying the gears l() and`13.The opposite side of this end of the journal lbearing has communicatingtherewith an -oblique duct 30 communicating at its opposite end throughthe inner face ofthe cylinder head with the teeth of the gear 10. ,Bymeans of these ducts 4the oil iindsits way to the journal 29 and to theteeth of gear 10 thence to the other gears within the gear case. Allthese ducts are, for convenience, located in the same ;vertic al plane.The main shaft is lubricated and`sealed by 'an oblique pont-31 extendingin a horizontal plane from' the -side of theAV journal bearing on thecountershaft to the bearing 32 and through which the main shaft extends.vThe suction port 21 is connected as usual to the. discharge port of'the' refrigerator indicated` at 41 by apipe40.

' To facilitate the spreading of the oil bel tween the various frictionsurfaces I form bearing ,of the counter shaft. These encircling chambersserve the double purpose lof lubricating and sealing the bearing andthusefectively prevent leaka e of gas. lTp .further augmentA thespreading ofy the o1l the end ofthe counter-shaft has a transverse igroove=52 in intercommunication'with the A adjacent encircling groove51.

In order to obviate any disturbance in the uniform flow of ,oil throughthe machine the initial supply port 25 is duplicatedfat- .the opposite?sides of the machine as shown in Fig. 1, and there are a pair ofstrainersv as shown in Fig. 5. The effect is that in the event of eitherof these ducts 25,'Wh1ch i both lead from the main oil chamber y', beingby the other duct.V f

blocked'the supply of oil will maintained Duringy he opera'tlon of thecompressor y. the gas beingcom ressed` passes throughl the upper part oft e internal oil chamber the oil and gas' separatorto the dis-A chargefitting t from which it flows by. pipe ,42 to the condenser 43 in theusual way and.

from Athe. condenser 'to 'the refrigerator through a pipe 44, acontroller 45` and a refrigerator charging pipe 46. The suction' exertedby the compressor dra-ws the expended gas from the refrigeratorthroughpipe 40.- This pipe 40 is provided with a check 70 valve to prevent oilleaking from the compressor through the pipe 40 as is liable to occurwhen the machine is stopped or for other reasons. It is well knownthatwhen the machine is' stopped the pressure in the pres- 75 sure endof the compressor is greater than the pressure in the suctionend andthere beingv no impelling force to check it, the gears being idle, theoil accumulated in chamber 2O and infact all'the oil in'the suction endof ,'80

started up the check Valve does not retard i the upward flow of gasthrough the ipe 40 to the suction port 21 and suction'cliamber 20. tothe gas compressing gears... During this yoperation the oilV circulatesthrough the various ducts, between the intermeshing surfaces of thegears, between thegears and wall presented by the cylinder head,partition 16 and innerv end of the gear case and f through the chambers20, 18, 17 and 19 and port 22 from which latter .it drops down in 95 theinternal` oil chamber and` joins the body of oil in the base of 'themachine. The com pressed gas passes through port 14 and. as it is in ameasure la'dened with oil it is made the discharge fitting. In thismanner the l gas is subjected 'to two stages of separation,

in the rst it tends to separate 'from the gas by gravitation and itdrops from-port 22.

By the structural features of 1n im- 105` proved rotarygas'compressor-it will ob?- served, an internal lubricatin s stem is provided, the oilfloods the sha earings .and consequently hermetically seals themagainst' escape of gas there, the two stages of sepadischarge fittingensures the supply of gas entirely'free from oil, while in the event ofthe machlne being shut down or'the pressure at the suction ports, 'forother/reasons, dropping below vthe pressure, at the inner end of themachine, the tendency of oil to leak into the suction check -valve 50.

What I claim is as follows:

1.v A rotary gas compressor comprising a cyhnder havingv an inlet'fortheas to be com ressed, a cylindrical oil cham r with-v in -t ecylinderfand containing rotary gas compressingmembers; a shallow-horizontal Ioil chamber between the bottom of the cylindrical oilchamber 4and the base ofr the cylinder; and aA verticalas and oilpassage between the inner end cfg ration of the oil from thegas duringits 4 ntransit from the compressing gears 'to the pipe 1s checked byvthe 120 the cylindrical oil 13 .a gas discharge fitting,

chamber and the corresponding end of the cylinder; the oil chamber inthe base having an oil' intake, the top ofthe passage having and theinner wall of the cylindrical oil chamber having` a gas discharge portand a port effecting communication between the oil chambersandconstitutingtherewith a closed lcircuit within i the cylinder and Ymber and all friction surfaces, tial oil `connection between the oilchamber in lthe base and the oil containing spaces -within thecompresor.

2. rotary gas compressor such as claimed in claim 1, having an oil andgas separator within the upper end of the oil and gas passage, suchseparator consisting of va series of baille plates located at said orts.p

3L rotar.)7 gas compressor comprising a Vhousing having a basecontaining a relatively shallow oil' chamber, an upwardly curved 'topAand an internal downwardly curved horizontal partition concentric toand forming an integral continuation of the the level of the top andconstituting with the top a cylinder compressed; and such.

Apartiallnjvithin the sides of the housing,

such cy der having Van inlet for the gas to including the said oil cham`a duplex in- 1 sides extendingdownwardly from the sides of the cylinderthus formed to and merging in the base, a vertical wall closing theinner end of the cylinder and having therein a gas discharge ort nearits upper end and an oil port near its lower end, both ofthe said portscommunicating with the interior of the cylinder, the cyhnder headclosing the cylinder, va vertica transverse wall formed integrally withthe adjacentend of the base and connecting the same to the cylinder, avertical transverse wall formed integrally with the opposite end theouter end of l of the base and lspaced from that end `of the cylinderandextending upwardly to a point above the cylinder top and having sidesextending to and merging in the cyl-- inder -wall and forming a verticaloil and gas passage, a discharge fitting mounted on thev top `of' thesaid passage,` the cylinder containing rotary gas compressing members,means for operating the gas compressing members, a lubricating system ina, closed circuit within the housing and including the oil chambersandall friction surfaces and shaft bearings.

In testimony name.

l l CARL W. YOLLMANN. A

whereof I have signed my

